X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/58a4ab67fc75b62968634cddec290c1f2e2c1ded..f64a4a5f49bcbcb996820b566d7ffe9f7cefe4f3:/print-eap.c diff --git a/print-eap.c b/print-eap.c index 5d722ec7..f8e04d58 100644 --- a/print-eap.c +++ b/print-eap.c @@ -26,6 +26,7 @@ #include "netdissect-stdinc.h" +#define ND_LONGJMP_FROM_TCHECK #include "netdissect.h" #include "extract.h" @@ -42,11 +43,11 @@ struct eap_frame_t { }; static const struct tok eap_frame_type_values[] = { - { EAP_FRAME_TYPE_PACKET, "EAP packet" }, - { EAP_FRAME_TYPE_START, "EAPOL start" }, - { EAP_FRAME_TYPE_LOGOFF, "EAPOL logoff" }, - { EAP_FRAME_TYPE_KEY, "EAPOL key" }, - { EAP_FRAME_TYPE_ENCAP_ASF_ALERT, "Encapsulated ASF alert" }, + { EAP_FRAME_TYPE_PACKET, "EAP packet" }, + { EAP_FRAME_TYPE_START, "EAPOL start" }, + { EAP_FRAME_TYPE_LOGOFF, "EAPOL logoff" }, + { EAP_FRAME_TYPE_KEY, "EAPOL key" }, + { EAP_FRAME_TYPE_ENCAP_ASF_ALERT, "Encapsulated ASF alert" }, { 0, NULL} }; @@ -77,9 +78,9 @@ static const struct tok eap_code_values[] = { #define EAP_TYPE_MD5_CHALLENGE 4 #define EAP_TYPE_OTP 5 #define EAP_TYPE_GTC 6 -#define EAP_TYPE_TLS 13 /* RFC 2716 */ +#define EAP_TYPE_TLS 13 /* RFC 5216 */ #define EAP_TYPE_SIM 18 /* RFC 4186 */ -#define EAP_TYPE_TTLS 21 /* draft-funk-eap-ttls-v0-01.txt */ +#define EAP_TYPE_TTLS 21 /* RFC 5281, draft-funk-eap-ttls-v0-01.txt */ #define EAP_TYPE_AKA 23 /* RFC 4187 */ #define EAP_TYPE_FAST 43 /* RFC 4851 */ #define EAP_TYPE_EXPANDED_TYPES 254 @@ -89,23 +90,23 @@ static const struct tok eap_type_values[] = { { EAP_TYPE_NO_PROPOSED, "No proposed" }, { EAP_TYPE_IDENTITY, "Identity" }, { EAP_TYPE_NOTIFICATION, "Notification" }, - { EAP_TYPE_NAK, "Nak" }, + { EAP_TYPE_NAK, "Nak" }, { EAP_TYPE_MD5_CHALLENGE, "MD5-challenge" }, - { EAP_TYPE_OTP, "OTP" }, - { EAP_TYPE_GTC, "GTC" }, - { EAP_TYPE_TLS, "TLS" }, - { EAP_TYPE_SIM, "SIM" }, - { EAP_TYPE_TTLS, "TTLS" }, - { EAP_TYPE_AKA, "AKA" }, - { EAP_TYPE_FAST, "FAST" }, + { EAP_TYPE_OTP, "OTP" }, + { EAP_TYPE_GTC, "GTC" }, + { EAP_TYPE_TLS, "TLS" }, + { EAP_TYPE_SIM, "SIM" }, + { EAP_TYPE_TTLS, "TTLS" }, + { EAP_TYPE_AKA, "AKA" }, + { EAP_TYPE_FAST, "FAST" }, { EAP_TYPE_EXPANDED_TYPES, "Expanded types" }, { EAP_TYPE_EXPERIMENTAL, "Experimental" }, { 0, NULL} }; -#define EAP_TLS_EXTRACT_BIT_L(x) (((x)&0x80)>>7) +#define EAP_TLS_EXTRACT_BIT_L(x) (((x)&0x80)>>7) -/* RFC 2716 - EAP TLS bits */ +/* RFC 5216 - EAP TLS bits */ #define EAP_TLS_FLAGS_LEN_INCLUDED (1 << 7) #define EAP_TLS_FLAGS_MORE_FRAGMENTS (1 << 6) #define EAP_TLS_FLAGS_START (1 << 5) @@ -149,15 +150,25 @@ static const struct tok eap_aka_subtype_values[] = { void eap_print(netdissect_options *ndo, const u_char *cp, - u_int length) + const u_int length) { u_int type, subtype, len; - int count; + u_int count; + const char *sep; + ndo->ndo_protocol = "eap"; type = GET_U_1(cp); len = GET_BE_U_2(cp + 2); - if(len != length) { - goto trunc; + ND_ICHECK_U(len, <, 4); + if (len != length) { + /* + * Probably a fragment; in some cases the fragmentation might + * not put an EAP header on every packet, if reassembly can + * be done without that (e.g., fragmentation to make a message + * fit in multiple TLVs in a RADIUS packet). + */ + ND_PRINT("EAP fragment?"); + return; } ND_PRINT("%s (%u), id %u, len %u", tok2str(eap_code_values, "unknown", type), @@ -169,6 +180,7 @@ eap_print(netdissect_options *ndo, if (type == EAP_REQUEST || type == EAP_RESPONSE) { /* RFC 3748 Section 4.1 */ + ND_ICHECK_U(len, <, 5); subtype = GET_U_1(cp + 4); ND_PRINT("\n\t\t Type %s (%u)", tok2str(eap_type_values, "unknown", subtype), @@ -176,58 +188,63 @@ eap_print(netdissect_options *ndo, switch (subtype) { case EAP_TYPE_IDENTITY: - if (len > 5 ) { + /* According to RFC 3748, the message is optional */ + if (len > 5) { ND_PRINT(", Identity: "); nd_printjnp(ndo, cp + 5, len - 5); } break; case EAP_TYPE_NOTIFICATION: - if (len > 5) { - ND_PRINT(", Notification: "); - nd_printjnp(ndo, cp + 5, len - 5); - } + /* According to RFC 3748, there must be at least one octet of message */ + ND_ICHECK_U(len, <, 6); + ND_PRINT(", Notification: "); + nd_printjnp(ndo, cp + 5, len - 5); break; case EAP_TYPE_NAK: - count = 5; - /* * one or more octets indicating * the desired authentication * type one octet per type */ - while (count < (int)len) { - ND_PRINT(" %s (%u),", + ND_ICHECK_U(len, <, 6); + sep = ""; + for (count = 5; count < len; count++) { + ND_PRINT("%s %s (%u)", sep, tok2str(eap_type_values, "unknown", GET_U_1((cp + count))), GET_U_1(cp + count)); - count++; + sep = ","; } break; case EAP_TYPE_TTLS: case EAP_TYPE_TLS: + ND_ICHECK_U(len, <, 6); if (subtype == EAP_TYPE_TTLS) ND_PRINT(" TTLSv%u", EAP_TTLS_VERSION(GET_U_1((cp + 5)))); - ND_PRINT(" flags [%s] 0x%02x,", + ND_PRINT(" flags [%s] 0x%02x", bittok2str(eap_tls_flags_values, "none", GET_U_1((cp + 5))), GET_U_1(cp + 5)); if (EAP_TLS_EXTRACT_BIT_L(GET_U_1(cp + 5))) { - ND_PRINT(" len %u", GET_BE_U_4(cp + 6)); + ND_ICHECK_U(len, <, 10); + ND_PRINT(", len %u", GET_BE_U_4(cp + 6)); } break; case EAP_TYPE_FAST: + ND_ICHECK_U(len, <, 6); ND_PRINT(" FASTv%u", EAP_TTLS_VERSION(GET_U_1((cp + 5)))); - ND_PRINT(" flags [%s] 0x%02x,", + ND_PRINT(" flags [%s] 0x%02x", bittok2str(eap_tls_flags_values, "none", GET_U_1((cp + 5))), GET_U_1(cp + 5)); if (EAP_TLS_EXTRACT_BIT_L(GET_U_1(cp + 5))) { - ND_PRINT(" len %u", GET_BE_U_4(cp + 6)); + ND_ICHECK_U(len, <, 10); + ND_PRINT(", len %u", GET_BE_U_4(cp + 6)); } /* FIXME - TLV attributes follow */ @@ -235,7 +252,8 @@ eap_print(netdissect_options *ndo, case EAP_TYPE_AKA: case EAP_TYPE_SIM: - ND_PRINT(" subtype [%s] 0x%02x,", + ND_ICHECK_U(len, <, 6); + ND_PRINT(" subtype [%s] 0x%02x", tok2str(eap_aka_subtype_values, "unknown", GET_U_1((cp + 5))), GET_U_1(cp + 5)); @@ -252,8 +270,9 @@ eap_print(netdissect_options *ndo, } } return; -trunc: - nd_print_trunc(ndo); + +invalid: + nd_print_invalid(ndo); } void @@ -265,7 +284,6 @@ eapol_print(netdissect_options *ndo, ndo->ndo_protocol = "eap"; eap = (const struct eap_frame_t *)cp; - ND_TCHECK_SIZE(eap); eap_type = GET_U_1(eap->type); ND_PRINT("%s (%u) v%u, len %u", @@ -282,10 +300,10 @@ eapol_print(netdissect_options *ndo, switch (eap_type) { case EAP_FRAME_TYPE_PACKET: if (eap_len == 0) - goto trunc; + goto invalid; ND_PRINT(", "); eap_print(ndo, cp, eap_len); - return; + break; case EAP_FRAME_TYPE_LOGOFF: case EAP_FRAME_TYPE_ENCAP_ASF_ALERT: default: @@ -293,6 +311,6 @@ eapol_print(netdissect_options *ndo, } return; - trunc: - nd_print_trunc(ndo); +invalid: + nd_print_invalid(ndo); }